THE FREQUENCY OF Kell Red Cell Antigens (K&k) Among THE Major SUDANESE TRIBES

Abstract

The Kcll blood group system is complex containing over 20 different antigens with high and low incidence. The Kell antigens are located on a single red cell transmembrane glycoprotein, encoded by 19 exons of the Kcll gene. Kell gene is carried on chromosome 7 and is located at 7q33. Kell blood group system is the most important blood group antigens after Rh antigen because the Kell antigens are highly immunogenic and the corresponding antibodies are significant in transfusion reactions and HDN. This study was carried out on 500 random samples to determine the frequency of Kell-l and Kell-2 and their gene frequencies among the major Sudanese tribes (Shaigia-Dinka- Gaalien - Nuba -— Bani-amer), during the period of April 2004 and April 2006. One hundred volunteers from each tribe. Each sample was tested for Kell-1 and Kell-2 by indirect Combs’ test using anti-Kell-1 and Kell-2 antisera. The study group had an age average between ll and 75 years with amean of 28 years. The frequency of Kell-1 was found to be 5.6% while that of Kell-2 was found to be 99.6%. Gene frequencies of Kell-1 and Kell-2 were found to be 0.03 and 0.97 respectively. Percent positivity for the phenotypes K-k+, K+k+ and K+k- were found to be 94.4%, 5.2% and 0.4% respectively. The gene frequencies of K-k+, K+k+ and K+k- phenotypes were found to be 0.941, 0.058 and 0.0009 respectively. All multi-gravida females with history of HDN as well as multi- transfused patients should be reserved for anti-Kell antibodies. All units of blood to be transfused to Kell-1 sensitized patients must be Kell genotyped.